Great questions! Don't hesitate to ask anything.

Typically when talking about worm harnesses and 60" leaders, they are referring to a 60" mono line with swivels on each end.

Personally I use braided line with a swivel on the end, then snap on a True Trip Diver, then a 60" Mono Leader, then a worm harness or spoon... etc...

The leader is that long for several reasons, but mainly to give distance between my diver and my lure. Sometimes we put weights in line, then the leader... Depends on the lure and the fish.They also give some "shock" absorption when running braided line. Although 60" doesn't tend to lead to a lot of shock absorption...

-Matt